arXiv AI

Chance-Constrained Inspection Viewpoint Sequencing for On-Orbit Servicing via Safe Reinforcement Learning

arXiv AI
Oct 31

Where Planning Changes the Outcome of Orbital Games

The paper introduces OrbitalGym, a JAX‑based simulation environment for studying how planning algorithms and system design influence the outcomes of adversarial orbital encounters. It supports multiple agents, diverse state representations, communication modes, and sensor models, and compiles games to batched GPU code for large‑scale parallel simulation. Using OrbitalGym, the authors evaluate several control policies (PD, LQR, MPC, MCTS) across two close‑range games—pursuit‑evasion and lady‑bandit‑guard—showing that propellant availability often dominates in pursuit‑evasion, while policy choice significantly improves defense in the lady‑bandit‑guard scenario.

By Duncan Eddy, Mahdi Al-Husseini, Mykel J. Kochenderfer
arXiv AI
Sep 15

Chance-Constrained Belief-Space Maneuver Planning for Autonomous Collision Avoidance Under Uncertainty

The paper presents a chance-constrained belief-space planning framework for autonomous collision avoidance in low Earth orbit. It models uncertain orbital states as Gaussian beliefs and uses a Monte Carlo tree search to decide whether to wait for better tracking data or to execute a maneuver before the time of closest approach. Experiments on 96 scenarios from NASA’s dataset show that the planner can avoid maneuvers in about 40% of cases while keeping collision risk below the threshold, with performance heavily dependent on tracking quality and cadence.

By Grace Ra Kim, Duncan Eddy, Mykel J. Kochenderfer
arXiv Machine Learning
Aug 11

Satellite Trajectory Optimization via Proximal Policy Optimization for Space Debris Avoidance

arXiv:2608. 09628v1 Announce Type: new Abstract: Collision avoidance systems are commonly used to avoid fragmentation events occurring in Low-Earth Orbit (LEO) and Geosynchronous Equatorial Orbit (GEO).

By Logan Luna (Georgia Institute of Technology), Juan Ortiz Couder (Embry-Riddle Aeronautical University), Raul Alejandro Vargas-Acosta (Embry-Riddle Aeronautical University)
arXiv Machine Learning
Oct 3

Reachability-Informed Reinforcement Learning for Multi-Impulse Interplanetary Transfers

The paper introduces Reachability Analysis-Informed Reinforcement Learning (RARL) for designing deterministic multi‑impulse interplanetary transfers. RARL uses local first‑order reachability maps to bound velocity perturbations and selects intermediate waypoints, which are then translated into maneuvers via Lambert reconstruction and a terminal two‑impulse solution. Numerical experiments on an Earth‑Mars benchmark show that RARL achieves a mean maneuver cost only 1.72% above a validated convex programming reference and can be trained once to handle a wide range of departure states, achieving 100% feasibility on 10,000 held‑out Monte Carlo departures.

By Yashdeep Chaudhary, Roberto Armellin, Harry Holt
arXiv AI
Oct 26

PPO vs. SAC: A Comparative Study for Cooperative Motion Control of Dual-Arm Space Robots

The paper compares Proximal Policy Optimization (PPO) and Soft Actor-Critic (SAC) for cooperative motion planning of dual‑arm space manipulators tasked with reaching a target while avoiding inter‑arm collisions. A centralized state representation and multi‑objective reward function are used, and SAC consistently outperforms PPO across five random seeds, achieving an 80% success rate within 1.6 M steps versus PPO’s failure to reach this threshold within 4 M steps. Both algorithms degrade on unseen boundary targets, but SAC retains most of its performance while PPO collapses, revealing a reward‑loitering failure mode for PPO. whyItMatters":"The study demonstrates that off‑policy SAC is more robust and effective than on‑policy PPO for coordinating dual‑arm space robots, informing algorithm choice for active debris removal and on‑orbit servicing tasks."

By Nasim Fallahiarezoodar, Zheng H. Zhu
arXiv AI
Jul 21

Learning Adaptive Safety Margins for Visual Navigation

arXiv:2607. 18200v1 Announce Type: cross Abstract: Robots in cluttered indoor spaces often fail not because they cannot generate collision-free paths, but because a fixed safety margin is mis-calibrated: conservative margins cause detours and timeouts, while permissive margins lead to near-boundary shortcuts under perception bias.

By Junyi Hu, Shuaihang Yuan, Geeta Chandra Raju Bethala, Anthony Tzes, Yi Fang
arXiv Machine Learning
Sep 3

Exchange Policy Optimization Algorithm for Semi-Infinite Safe Reinforcement Learning

The paper introduces Exchange Policy Optimization (EPO), a framework for semi‑infinite safe reinforcement learning that handles infinitely many constraints by iteratively solving finite subproblems. EPO expands or deletes constraints based on tolerance violations and Lagrange multipliers, maintaining computational tractability while converging to an optimal policy with bounded safety violations. The authors prove finite convergence, provide iteration bounds, and quantify the suboptimality gap under mild assumptions.

By Jiaming Zhang, Yujie Yang, Haoning Wang, Liping Zhang, Shengbo Eben Li
arXiv Machine Learning
Oct 16

Feasibility Ceilings Before Learning: Sizing and Timing Bounds for Drone-Mesh Interception

The paper derives closed‑form bounds on the performance of a drone‑mesh interception system before any learning policy is applied. It shows that, due to a separation constraint, a mesh of agents can cover at most 90.69 % of a plane (74.05 % of a volume) and that optimal hexagonal packing achieves this limit. The authors validate these theoretical ceilings with Monte‑Carlo simulations and argue that such bounds should be reported alongside any learning‑based results.

By Dmytro Babarytskyi
arXiv Machine Learning
Sep 29

Learning Chance-Constrained MDPs with Bellman Distributional Certificates

The paper introduces a new approach to learning chance-constrained Markov decision processes (CCMDPs) using a Bellman distributional certificate. It provides both model-based and model-free algorithms with theoretical guarantees, including matching upper and lower bounds for tabular discounted CCMDPs with bounded successor support. Numerical experiments on synthetic CCMDPs and an IEEE 14-bus energy storage benchmark demonstrate the safety and effectiveness of the proposed methods.

By Chenbei Lu, Hongyu Yi